View full sizeDonald Gilliland, The Patriot-News, 2010One of Chesapeake Energy's Marcellus Shale wells sits high on a bluff over the Susquehanna River in Windham Township, Wyoming County, Pennsylvania.

Officials with DEP had asked the source of the photo — the stock image website Shutterstock — for details of the pipe’s location — to make certain it was not a pollution event in Pennsylvania.

Vincent Jansen, manager of contributor relations for Shutterstock, wrote in an email to DEP: “The (photographer) is from South Africa, so it is very unlikely that this image was taken in the United States.”

PennEnvironment last September published a photo of a flooded drilling rig in Pakistan purporting it to be a rig in Pennsylvania's Marcellus Shale during flooding from Tropical Storm Lee. The group later apologized.

PennEnvironment on Thursday took no responsibility for the South African photo on the cover of its report, blaming the contractor that produced the report, the Frontier Group of Boston.

At the Frontier Group, the report’s lead author, Rob Keth, said he was not aware that the pipe was not discharging toxic industrial sludge into an actual river. He said he had simply searched the website, found the photo and used it — without checking other photos from the same photographer or making any other effort to verify its accuracy.

On Friday, the Frontier Group had removed the photo from its website and posted the following apology:

"The photo used on the cover of this report is a stock photo, which was represented by the stock photo agency as a pollution discharge into a river. It was not. Frontier Group regrets the error. Stock photos are often used by companies and organizations as elements of graphic design rather than vehicles for editorial content, and Frontier Group is far from alone in this practice. We do, however, aim for a higher standard to ensure that even stock photos are editorially relevant to the issue discussed in the report. This was a standard that was not met in this case and we regret the mistake."

The report itself decries the volume of pollutants discharged into American rivers.

Those are legal and permitted discharges reported to the U.S. Environmental Protection Agency, from which the Frontier Group got its data.

But the report argues that regulators should make permits more stringent to reduce pollutants and improve water quality.

“Pennsylvania rivers have come a long way and are in much better shape than 30 years ago, but there’s still work to be done,” said Karns.

He called the choice of cover photo for the report “really unfortunate.”

“I can see the ease of going to a stock photo site and clicking on the first thing that looks good,” said Karns, “but I think it’s important to have visual representation that matches the facts in the document.”

The report also has been criticized by environmentalists for misleading content.

The Pittsburgh Tribune Review quoted a lawyer with the Environmental Law and Policy Center in Chicago saying, "The report does not specify what toxics are in the waterways. It also talks about nitrates, which are generally from agricultural runoff. They are a big problem, but they are not toxic or from heavy industry."